1. Field of the Invention
The present invention relates to computer databases.
2. Related Art
A query causes a set of objects from a computer database to be presented. A query can be defined in terms of a feature associated with the set and/or a range of values associated with the feature. When the set is associated with more than one feature, Boolean algebra expressions can be used to indicate the relationships among the features. As database technology has evolved, query languages have been developed to allow a user to construct a query. Furthermore, a user interface can be used so that the user can construct the query without specific knowledge of the underlying query language. Typically, a graphical user interface can be used to construct a simple query. However, a character user interface is often necessary to construct a more complex query. This is particularly the case when the user interface supports queries of a computer database in which a set of objects can have more than one feature, in which the values associated with any one feature can reside within a range of values. To construct such queries, a character user interface is often used to select a subrange of values of the feature. Typically, the lower and upper limits of the subrange are keyed into the query via the character user interface. What is needed is a graphical user interface that can construct queries for a computer database in which a set of objects can have more than one feature, in which the values associated with any one feature can reside within a range of values.